Pydev Can't Debug Anymore

I'm using eclipse 4.2.1 and pydev 2.7.1 (previously 2.6.0) Everything was working fine, until suddenly the debugger stopped working - it prints 'pydev debugger: starting' and then

Solution 1:

I found that removing .metadata/.plugins/org.eclipse.core.resources from the workspace solves the problem.. but it also removes all the projects so I had to reimport them.